1. Field of the Invention
The present invention relates to a method and apparatus for spreading a liquid slurry, and more particularly, to spreading fertilizer in a field.
2. Description of the Prior Art
It is quite common for farmers to collect animal manure in a lagoon next to a barn in which animals are kept, and to recycle the manure as fertilizer for vegetable growing fields, such as in corn fields or the like. Presently, the manure is pumped from the lagoon as a slurry (using a pumping device as described in U.S. Pat. No. 4,594,006, issued Jun. 10, 1986, and U.S. patent application Ser. No. 434,909, filed Nov. 9, 1989 in the name of the applicant), into a tank mounted on a vehicle, and the vehicle, either self-propelled or a trailer drawn by farm tractor, is passed through a corn field spreading the slurry on the soil surface. In some cases, particularly if the stalks of corn have sprouted above the ground surface, in rows, coinciding with the planting furrows, care is taken to ensure that the vehicle wheels pass in paths between the furrows, and the delivery of the manure slurry is directed by nozzles onto the paths between the furrows.
In these cases, the manure is spread on the surface and thus the fertilization is dependent on the amount of slurry which seeps or leaches into the earth, assuming it does not get washed away by rain water or drained because of the slope of the land.